A catheter assembly for navigation including a flexible catheter having a proximal portion adjacent a proximal end and a distal portion adjacent a distal end and defining a longitudinal axis, the flexible catheter defining a lumen extending therethrough along a longitudinal axis and configured to enable translation of an instrument from the proximal end to the distal end. The flexible catheter defines a compound curve formed on the distal portion, wherein the compound curve includes an elbow bend and a radially curved portion. The elbow bend deflecting the distal portion of the flexible catheter from the longitudinal axis, while the radially curved portion extends from the elbow bend farther deflecting the distal portion about a center point. The catheter guide assembly for navigation includes a control handle disposed at the proximal end of the flexible catheter and is configured to advance and rotate the flexible catheter within a luminal structure.